Specific nitration of tyrosines 46 and 48 makes cytochrome c assemble a non-functional apoptosome
Under nitroxidative stress, a minor fraction of cytochrome c can be modified by tyrosine nitration. Here we analyze the specific effect of nitration of tyrosines 46 and 48 on the dual role of cytochrome c in cell survival and cell death. Our findings reveal that nitration of these two solvent-expose...
| Autores: | , , , , , , |
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| Formato: | artículo |
| Estado: | Versión aceptada para publicación |
| Fecha de publicación: | 2012 |
| País: | España |
| Recursos: | Universidad de Sevilla (US) |
| Repositorio: | idUS. Depósito de Investigación de la Universidad de Sevilla |
| OAI Identifier: | oai:idus.us.es:11441/70835 |
| Acesso em linha: | https://hdl.handle.net/11441/70835 https://doi.org/10.1016/j.febslet.2011.12.007 |
| Access Level: | acceso abierto |
| Palavra-chave: | Mitochondrial respiration Electron transfer Cytochrome c oxidase Tyrosine nitration Caspase-9 activation Post-translational modification RNOS Cytochrome c Apoptosome |
| Resumo: | Under nitroxidative stress, a minor fraction of cytochrome c can be modified by tyrosine nitration. Here we analyze the specific effect of nitration of tyrosines 46 and 48 on the dual role of cytochrome c in cell survival and cell death. Our findings reveal that nitration of these two solvent-exposed residues has a negligible effect on the rate of electron transfer from cytochrome c to cytochrome c oxidase, but impairs the ability of the heme protein to activate caspase-9 by assembling a non-functional apoptosome. It seems that cytochrome c nitration under cellular stress counteracts apoptosis in light of the small amount of modified protein. We conclude that other changes such as increased peroxidase activity prevail and allow the execution of apoptosis. |
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